He isn't wasn't wrong, and the parent post wasn't even correcting him. Gmail is not a corporation, it is a product - singular.
Can you "shame" a product, though? Obviously not. So you're shaming the people who built Gmail, the organization - hence the plural form is acceptable.
Gmail is a product, but the comment wasn't saying "Gmail the product deserves to be shamed... ", more like "the Gmail team/devs/company deserves to be shamed...", which is why the plural still made sense to me (given the omission of an explicit "team"). The singular makes sense to me too.
In any case, I wasn't really interested in correcting or proving anyone right or wrong, just pointing out an interesting linguistic detail and where the grammar may have come from.